Synthetic organic fibers coated with an amino silane and an epoxy siloxane containing treating agent

ABSTRACT

A treating agent for filling synthetic fibers, said treating agent comprising (a) 1 part by weight of a specific substituted aminosilane of the formula ##STR1## and (b) 1 to 20 parts by weight of a specific epoxysiloxane containing at least one structural unit of the formula ##STR2## and at least two structural units of the formula ##STR3## A method for treating synthetic fibers with the above treating agent. Synthetic fibers treated with the above treating agent suitable for use as fillings for quilts.

This application is a division of application Ser. No. 604,047, filedAug. 12, 1975, now U.S. Pat. No. 3,980,599, which in turn iscontinuation-in-part of Ser. No. 546,906 filed Feb. 4, 1975 nowabandoned.

This invention relates to a treating agent for synthetic fibers for useas filling or stuffing, a process for treating synthetic fibers withsuch treating agent, and to synthetic fibers for filling obtained bytreatment with the treating agent. More specifically, the inventionrelates to a treating agent for filling synthetic fibers which havesuperior compression elasticity, slickness, suppleness, soft feelsimilar to feather quilt, and wearing fitness, a process for treatingsynthetic fibers with such treating agent, and to filling syntheticfibers obtained by treatment with the treating agent.

Cotton and feathers have been the chief conventional filling for bedquilts or the like, and because of especially superior compressionelasticity, slickness, suppleness and feel of the feathers, bed quiltsusing feathers as filling have been used as luxuries.

In recent years, such filling has been superseded by synthetic fiberssuch as polyester fibers or polypropylene fibers. However, fillingscomposed of such synthetic fibers have inferior compression elasticity,slickness, suppleness and feel to feathers, and present poor fitness tothe body when used in bed quilts.

It has been attempted to produce luxury bed quilts having goodcompression elasticity and soft feel by changing the fibrous arrangementof the filling using synthetic fibers. For example, an attempt was madeto use synthetic fibers in the form of tows instead of staples. However,this proposed method does not result in a substantial change of theproperties of the fibers, and bed quilts obtained are not comparable tothe feather quilts although exhibiting better compression elasticity,suppleness and feel than bed quilts using the conventional syntheticfiber fillings in staple form. In addition, this method has anotherdefect in that since the fibers are used in tow form, conventionalmethods for producing bed quilts cannot be applied as such.

Without any effective and decisive solution to the problem, the currentpractice is to use synthetic fiber fillings treated with a treatingagent composed chiefly of a surface active agent. For example, JapaneseLaid-Open patent application No. 67592/73 discloses a treating agentcomposed of 80 to 60% by weight of a potassium salt of an ethylene oxide(2 mols) added lauryl phosphoether and 40 to 20% by weight of apropylene glycol ethylene oxide random copolymer having an averagemolecular weight of 24,000 in which 5 mols of ethylene oxide adds to 1mol of propylene glycol. Synthetic fiber fillings treated with thistreating agent cannot possess compression elasticity, suppleness andfeel similar to feathers.

We therefore attempted to treat synthetic fibers for filling with thesynthetic textile fiber treating agents which were previously proposedwith a view to impart slickness and suppleness similar to animal fiberssuch as alpaca and mohair to synthetic fibers. For example, we used thetreating agent disclosed in U.S. Pat. No. 3,655,420 to Robert L.Tichenor, which is a mixture of about 0.3 to 20 parts by weight of aliquid epoxysiloxane and 1 part by weight of an amine compoundcontaining at least two amino groups per molecule and not more than onearomatic ring directly bonded to the nitrogen atom.

Although this mixture imparts superior compression elasticity, slicknessand suppleness to synthetic fibers, it has the serious defect thatbecause of its strong activity, this mixture has poor storage stability;when allowed to stand in the form of emulsion, it gradually undergoescross-linkage at room temperature, and in about 2 or 3 days, it isdegenerated. When this treating agent is used recyclically, it does notensure a uniform treatment because of the crosslinking that occurs at anelevated temperature during the operation, and the cross-linked treatingagent often adheres firmly to rollers or other treating devices, makingit necessary to interrupt the operation frequently.

Accordingly, a primary object of this invention is to provide a treatingagent for synthetic fibers which gives synthetic fiber fillings havingsuperior properties such as compression elasticity, slickness,suppleness, soft feel and wearing fitness.

Another object of this invention is to provide a process for treatingfilling synthetic fibers using such a treating agent.

Still another object of this invention is to provide filling syntheticfibers treated with the above treating agent and having superiorcompression elasticity, slickness, suppleness, feed and wearing fitnesswhich give bed quilts comparable to feather quilts.

A further object of this invention is to provide bed quiltings havingthe above superior properties.

Other objects of this invention along with its features and advantageswill become apparent from the following description.

According to this invention, there is first provided a treating agentfor filling synthetic fibers comprising

a. 1 part by weight of an aminosilane of the following formula (I)##STR4## wherein R₁ is a hydrogen atom, an alkyl group containing 1 to 4carbon atoms or a phenyl group, R₂ is an alkylene group containing 1 to4 carbon atoms, and R₃, R₄ and R₅, independently from each other,represent an alkyl group containing 1 to 4 carbon atoms, and

b. 1 to 20 parts by weight of an epoxysiloxane containing at least onestructural unit of the formula (II) ##STR5## wherein R₆ and R₇,independently from each other, represent an alkyl group containing 1 to3 carbon atoms, and at least two structural units of the formula (III)##STR6## wherein R₈ is an alkyl group containing 1 to 3 carbon atoms orthe group ##STR7##

R₉ being an alkylene group containing 2 to 5 carbon atoms or asubstituted or unsubstituted arylene group containing 6 to 10 carbonatoms.

The above treating agent has an effect of markedly reducing thecoefficient of friction of synthetic fibers for filling, and givesynthetic fiber fillings having superior compression elasticity,slickness, suppleness, feel and wearing fitness comparable to, orexcelling, feather quilts.

In the aminosilane of formula (I), the alkyl and alkylene groups mayeither be of straight chain or branched chain, and include, for example,methyl, ethyl n- or iso-propyl, n-, iso- or tert-butyl, methylene,ethylene, n- or iso-propylene, and n-iso- or tert-butylene groups.Methyl and ethyl groups are especially preferred as the alkyl group, andethylene and propylene groups are especially preferred as the alkylenegroup.

Some of the aminosilanes of formula (I) used in this invention are knowncompounds, and even novel aminosilanes of the above formula can beprepared in quite the same manner as the methods for preparing the knownaminosilanes.

Suitable aminosilanes include, for example,

aminomethyltrimethoxysilane,

β-aminoethyltrimethoxysilane,

β-aminoethyltriethoxysilane,

γ-aminopropyltrimethoxysilane,

γ-aminopropyltriethoxysilane,

δ-aminobutyltriethoxysilane,

β-methylaminoethyltriethoxysilane,

β-ethylaminoethyltriethoxysilane,

γ-methylaminopropyltrimethoxysilane,

γ-propylaminopropyltriethoxysilane,

γ-ethylaminobutyltriethoxysilane,

γ-phenylaminopropyltrimethoxysilane, and

γ-phenylaminopropyltriethoxysilane.

Of these, γ-aminopropyltriethoxysilane [H₂ NC₃ H₆ Si(OC₂ H₅)₃ ],γ-aminopropyltrimethoxysilane [H₂ NC₃ H₆ Si(OCH₃)₃ ],β-methylaminoethyltriethoxysilane [CH₃ NHC₂ H₄ Si(OC₂ H₅)₃ ] andγ-phenylaminopropyltrimethoxysilane [Ph--NHC₂ H₆ Si(OCH₃)₃ ] arepreferred. The γ-aminopropyltriethoxysilane is especially preferred.

In the treating agent of this invention, an epoxysiloxane having thefollowing recurring units ##STR8## is used in combination with theaminosilane of formula (I). In the above formulae, the alkyl groupsrepresented by R₆, R₇ and R₈ have 1 to 3 carbon atoms and may either beof straight chain or branched chain. The alkyl groups include methyl,ethyl, and n- or iso-propyl groups, of which a methyl group isespecially suitable. The alkylene group represented by R₉ may either beof straight chain or of branched chain, and contains 2 to 5 carbonatoms. For example, it includes ethylene, propylene, butylene, andpentylene groups, of which ethylene and propylene groups are especiallypreferred. R₉ may also be an arylene group, for example, phenylene andnaphthylene groups.

The group R₈ can also represent the group ##STR9## This means that theepoxysiloxane used in this invention can also contain a structural unitof the following formula ##STR10##

The epoxysiloxane that can be used in this invention needs to contain atleast one each of the recurring units of formulae (II) and (III),preferably at least 35, and more preferably 100 to 600, such units intotal, and at least two, preferably 4 to 20, of them must be recurringunits of formula (III).

Usually, the recurring units (II) and (III) and/or (IV) can be presentat random in the epoxysiloxane, but may also be present in a block form.A small amount of another recurring unit may be present in it so long asit does not considerably change the basic properties of theepoxysiloxane. The terminal groups can usually be trialkylsilyl orhydroxyalkylsilyl groups, but also silicon-free groups may be used. Whenthe molecules form a ring, the absence of terminal groups is alsopossible.

Desirably, the epoxysiloxane used in the treating agent of thisinvention is liquid and has a high molecular weight. Usually, it isadvantageous to use epoxysiloxane having a viscosity at 25° C. of 1,000to 100,000 centistokes, preferably 2,000 to 50,000 centistokes, mostpreferably 3,000 to 20,000 centistokes.

Preferably, the epoxisiloxanes used in this invention contain at least0.6% by weight of expoxy groups based on their total weight. The upperlimit of the epoxy group content is not critical, but usually, theamount of the epoxy groups is 0.6 to 10% by weight, preferably 1 to 5%by weight based on the total weight of the epoxy siloxane.

Epoxysiloxanes known per se can be used in this invention. For example,epoxysiloxanes of the type disclosed in the specification of U.S. Pat.No. 3,055,774 are useful.

The epoxy siloxanes must be water-soluble or readily dispersible inwater for convenience of use, but if desired, can be used in an organicsolvent or in the absence of solvent.

The epoxysiloxane described above can be used in a proportion of 1 to 20parts by weight, preferably 1 to 18 parts by weight, more preferably 2to 10 parts by weight, and most preferably 5 to 10 parts by weight, perpart by weight of the aminosilane of formula (I).

By adhering the treating agent of this invention to filling syntheticfibers, various characteristics suitable for filling purposes, such assuperior compression elasticity, slickness, suppleness, feel and wearingfitness can be imparted to the synthetic fibers.

Thus, according to this invention, there is provided a process fortreating synthetic fibers for filling, which comprises applying atreating agent comprising 1 part by weight of an aminosiloxane of theabove formula (I) and 1 to 20 parts by weight of an epoxysiloxanecontaining at least one structural unit of the above formula (II) and atleast two structural units of the above formula (III) and/or (IV) tosynthetic fibers for filling, and then heat-treating the fibers.

Adhering of the treating agent of this invention to filling syntheticresin can be performed by various known methods. The time of applicationmay be before or after a step of drawing synthetic fibers as-extruded,before or after a step of a crimping treatment, before or after a stepof bulking, before or after the above heat-treatment step, or before orafter a step of staple formation (cutting).

The treating agent can be used in the form of a solution in an organicsolvent, but usually, it is advantageous to use it in the form of anaqueous dispersion, especially an aqueous emulsion. The concentration ofthe aminosilane and the epoxy siloxane in such a solution or dispersioncan be varied over a wide range. The suitable concentration is 0.5 to20% by weight, preferably 1 to 15% by weight based on the weight of thesolution or dispersion. It should be understood that this concentrationrange, however, is not strictly critical, but depending upon the methodof application, the type of synthetic fibers, etc., concentrationsoutside the above range can also be employed.

Application of the treating agent to synthetic fibers can be performedby various means such as a dipping method, an oiling roller coatingmethod or a spray method. This results in the adhering or impregnatingof the treating agent of this invention to or in the synthetic fibers.

The amounts of the aminosilane and epoxysiloxane to be applied to fiberscan be varied over a wide range according to the specific effectdesired. Generally, it is suitable to apply them in a total amount,based on the dry weight of the fibers, of at least 0.1% by weight. Theupper limit is not particularly set, but the use of too large amountsdoes not bring about a corresponding effect, and is thereforeuneconomical. Usually, the total amount of the aminosilane and the epoxysiloxane applied is suitably not more than 3% by weight, preferably 0.2to 1.5% by weight, more preferably 0.3 to 1.0% by weight, based on thedry weight of the fibers.

When the treating agent of this invention is used in the form of anemulsion, an emulsifier or an antistatic agent, etc. can be blended inorder to facilitate the dispersion of the effective components. Examplesof preferred emulsifiers and antistatitc agents are anionic surfaceactive agents such as polyoxyethylene alkyl aryl ethers, polyoxyethylenealkyl ethers, polyoxyethylene sorbitan alkyl amides, polyvinyl alcohol,or their analogs, or alkyl phosphate potassium salts; and cationicsurface active agents such as quaternary ammonium salts (e.g., stearyldimethyl benzyl ammonium chlorideX, or stearylamide propyldimethyl3-hydroxyethyl ammonium nitrate.)

After applying the treating agent of this invention to fibers preferablyat a temperature of not more than 50° C., the fibers are heat-treated tocure and cross-link the aminosilane and the epoxysiloxane in thetreating agent on the surface of the fibers. This imparts markedlyimproved compression elasticity, slickness, suppleness, feel, andwearing fitness to the fibers. This heat-treatment also markedlyimproves the washing resistance of the fibers. The treating temperaturevaries according to the treating time, and cannot be unequivocallydetermined. If the temperature is too low, long periods of time arerequired to accomplish the heat-treatment and the effect obtained is notsufficient. On the other hand, if it is too high, the properties of thefibers are deteriorated. Thus, generally, the heat-treating temperatureis at least 100° C but below the melting point (or softening point) ofthe synthetic fibers, and temperatures of 100° to 230° C are especiallysuitable. The heat-treating time is at least 1 second, and can be variedover a wide range according to the heat-treating temperature. Whenrelatively high temperatures are used, it is advantageous to stop theheat-treatment within a short period of time that does not cause thedeterioration of the properties of the fibers. When polyethyleneterephthalate fibers are used, a period of about 10 minutes to 2 hoursis suitable at a temperature of 110° to 170° C., and a period of 1second to 10 minutes is most suitable when the temperature is 170° to230° C.

When the synthetic fibers treated by this invention are used asfillings, the fibers need to be crimped. The crimping treatment can becarried out before, during or after the treatment of the fibers inaccordance with this invention. It is preferred to crimp syntheticfibers to which the treating agent of this invention has been applied,before the heat-treatment in accordance with this invention. This hasthe advantage that both of the heat curing of the treating agent and theheat-setting of the crimps can be performed at the same time.

The crimping treatment can be carried out by various methods, forexample, mechanical crimping methods using a stuffer crimper, a gearcrimper, etc., or latent crimp-forming methods in which the crimps aredeveloped by heat-treatment or chemical treatment.

Usually, the fibers so treated are cut to suitable lengths.

Alternatively, the crimping treatment can be carried out after thetreatment of fibers in accordance with the method of this invention. Orit is also possible to apply the treating agent of this invention tofibers obtained by first crimping synthetic fibers and then, if desired,cutting them.

There is no particular limitation on the type of synthetic fibers towhich the treating agent and the treating method of this invention canbe applied, and examples of suitable synthetic fibers are polyester,polyamide, polyacrylic and polyolefin synthetic fibers. The polyesterfibers are especially suitable.

Thus, according to this invention, synthetic fibers coated with aheat-treated product of the aminosilane and the epoxysiloxane areobtained which have superior compression elasticity, slackness, andsuppleness and a soft feel. When these fibers are used as a filling ofbed quilts, they show a soft feel like feather quilts and afford goodwearing fitness.

The synthetic fibers treated by the method of this invention and crimpedand optionally cut can be utilized as fillings or stuffing of bedquilts, pillows or other quilts, etc. It has been found that when thesynthetic fibers satisfy the following properties, fillings of superiorquality can be provided by the favorable interaction between theproperties of the fibers and the treatment of this invention.

    1.5 ≦ D ≦ 10

    10 d - 20 ≦ l ≦ 10d + 60

    10 ≦ l

    -3/4d + 10.0 ≦ c.sub.n ≦ -3/4d + 15.5

    15 ≦ c.sub.n + c.sub.d ≦ 32

wherein

D is the denier size of the synthetic fibers;

L is the length of the fibers in mm,

C_(n) is the number of crimps per 25 mm, and

C_(d) is the percent crimp (%) (measured by the

method described in JIS L-1074).

Synthetic fibers, especially polyester fibers, having the aboveproperties and treated with the treating agent of this invention exhibitnot only superior compression elasticity, slickness, supplenesss, feeland wearing fitness, but all properties required of fillings ofstuffings such as a highest degree of handling properties by the abovesynergistic effect.

The denier (D) of the fibers is preferably 1.5 to 10 denier in view ofthe bulkiness of the filling and its handling properties (e.g., theoccurrence of neps in processing on cards). If suppleness is considered,the especially preferred denier size of the fiber is 2 to 8 denier. Whenfilling is prepared, fibers of different denier sizes as well as thesame sizes can be used.

If the length (L mm) of the fibers is too short, intertwining of thefibers is reduced at the time of producing fillings, and web breakagetends to occur. If it is too long, the fibers tend to wrap aroundcylinders of cards, and also to develop neps. In other words, thehandling properties of the fibers are degraded. Accordingly, it ispreferred that the length of the fibers should be:

    10D - 20 ≦ L ≦ 10D + 60

    10 ≦ l,

especially preferably

    10D - 10 ≦ L ≦ 10D + 50

    30 ≦ l.

as a measure for crimp characteristics, the number of crimps (C_(N),number/25 mm) and percent crimp (C_(D), %) are preferably within thefollowing range

    -34/ + 10.0 ≦ C.sub.N ≦ -3/4+ 15.5

    -3/4 15 ≦ c.sub.n + c.sub.d ≦ 32

more preferably within the following range

    -3/4D + 11.0 ≦ C.sub.N ≦ -3/4D + 14.5

    18 ≦ c.sub.n + c.sub.d ≦ 30.

if the crimp properties are below the lower limits of theabove-specified ranges, the handling properties of filling tends to bedeteriorated, and if they exceed the upper limits, the slickness offilling tends to be reduced. These crimp characteristics can be easilyimparted by, for example, conventional stuffer crimpers.

The treating agent of this invention can be equally applied to syntheticfibers used as filling in the form of tow.

Synthetic fibers to which the treating agent of this invention has beenapplied, and which, if desired, have been heat-treated and crimpedpossess very superior compression elasticity, slickness, suppleness,feel and wearing fitness, and have a wide range of utility as a fillingor stuffing material. When, for example, a bed quilt is prepared usingthese synthetic fibers, it exhibits superior feel and fittness to thebody comparable to or excelling those of feather quilts. If a pillow ora winter garment is produced using these sythetic fibers, it fits wellto the body.

The treating agent of this invention described above affords fillingsynthetic fibers having superior compression elasticity, slickness,suppleness, feel and wearing fitness which have not been provided by theconventional synthetic fibers, and can be applied not only to fillingpurposes, but also to other fields which require the abovecharacteristics. Accordingly, the treating agent of this inventionoffers a great commercial significance.

The following Examples further illustrate the present invention ingreater detail. In the Examples, all parts are parts by weight, and allviscosity values are expressed by centistokes at 25° C. The compressionelasticity, slickness and suppleness were evaluated by the followingmethods.

Compression elasticity

This is an important characteristic as filling. Especially in the caseof bed quilts the compression rate becomes a measure for the fittabilityto the body. It expresses the deformability of the fibers to the stresson the bedding. The higher the compression rate, the more deformable thefibers are in a bed quilt.

The compression elasticity is evaluated as follows:

A web is prepared by processing raw fibers on a card, and a samplehaving a cylindrical shape with a diameter of 10 cm and a weight of 20 gis made. A disc-like light load (0.5 g/cm²) and a disc-like heavy load(9.5 g/cm²) are placed on the sample and compressed for 10 minutes,after which the light and heavy loads are removed, and the sample isleft to stand for 2 hours. Again, the light and heavy loads are placedon the sample, and it is allowed to stand for 17 hours. The light andheavy loads are then removed, and after a lapse of 7 hours, only thelight load is placed on the sample. The height (h_(o)) of the sample atthis time is measured. Again, the light and heavy loads are placed onthe sample, and it is left to stand for 17 hours. The height (h₁) of thesample at this time is emeasured. Then, the light and heavy loads areremoved. After a lapse of 7 hours, only the light load is replaced andthe height (h₂) of the sample is measured.

The compression rate (%) and the compression recovery (%) are calculatedfrom the following equations. ##EQU1## In order for the filling toprovide soft feel and wearing fitness similar to feather quilts, it ispreferred that the compression rate is at least 70%, and the compressionrecovery is at least 90%.

Slickness

The slickness is evaluated by the coefficient of static friction (μs)between fiber and fiber and the coefficient of dynamic friction (μd)between fiber and fiber at a speed of 3 m/min. which are measured by theRoeder method at a temperature of 20° C. and a relative humidity of 65%.The smaller the μs and μd values, the better is the slickness.Preferably, both of the μs and μd values are not more than 0.25.

Feel

A sensual test is conducted for the feel of the filling in accordancewith this invention. 2.0 Kg of raw fibers spread on a card are uniformlyplaced in a bag of a belt quilt cloth with a size of 140 cm × 200 cm.The feel is evaluated both by hand and by wearing.

EXAMPLE 1

Polyethylene terephthalate having an intrinsic viscosity, as calculatedfrom the measured value in o-chlorophenol at 35° C., was melt-spun. Theresulting tow with a total denier of 400,000 (a single fiber denier of6) was dipped in a treating agent of each of the recipes shown in Table1 as an aqueous emulsion, squeezed by a stuffer crimper to a pick-up of10%, and dried at 90° C. for 20 minutes. Then, the two was heat-treatedat 140° C for 30 minutes, and cut to a fiber length of 76 mm.

The properties of the fibers obtained are shown in Table 2. The numberof crimps was 7 per 25 mm, and the percent crimp was 18% in all cases.

                  TABLE 1                                                         ______________________________________                                                           Treating agents (parts)                                    Composition          A      B      C    D                                     ______________________________________                                        γ-Aminopropyl triethoxysilane                                                                0.5                                                      γ-Aminopropyl trimethoxysilane                                                                      0.5                                               β-methylaminoethyl triethoxy- 0.5                                        silane                                                                        γ-Phenylaminopropyl trimethoxy-   0.5                                   silane                                                                        Epoxysilane - (1)*   4.9    4.9    4.9  4.9                                   Cetyl phosphate potassium salt                                                                     1.1    1.1    1.1  1.1                                   Polyoxyethylene (10 mols)                                                                          0.5    0.5    0.5  0.5                                   nonylphenol ether                                                             Water                93.0   93.0   93.0 93.0                                  ______________________________________                                    

The epoxysiloxane -(1)* used above consisted of structural units of thefollowing formulae ##STR11## and had a viscosity of 6,000 centistokes at25° C., an epoxy group content of 1% by weight with both ends beingtrimethylsilyl groups [--Si(CH₃)₃ ].

                  TABLE 2                                                         ______________________________________                                        Treating agent   A       B       C     D                                      ______________________________________                                        Slickness                                                                      μ s          0.17    0.17    0.18  0.19                                    μ d          0.16    0.17    0.17  0.20                                   Compression elasticity                                                         Compression rate                                                                              79      78      77    75                                      Compression recovery                                                                          99      99      97    95                                     Feel             Very similar to feather quilt                                ______________________________________                                    

COMPARATIVE EXAMPLE 1

A mixture of 60% by weight of a potassium salt of ethylene oxide (2mols)-added laurylphosphoether and 40% by weight of a propyleneglycol/ethylene oxide random copolymer having an average molecularweight of 24,000 in which 5 mols of ethylene oxide added to 1 mol ofpropylene glycol was formed into a 2% aqueous emulsion. The samepolyethylene tow as used in Example 1 was dipped in this treating agent,squeezed by a stuffer crimper to a pick up of 10%, heat-treated for 2hours at 140° C., and then cut to a length of 76 mm, and the percentcrimp was 18%. The fibers so treated had the following characteristics.

    ______________________________________                                        Slickness μ s   0.36                                                                 μ d   0.30                                                       Compression elasticity                                                         Compression rate                                                                            64%                                                             Compression recovery                                                                        88%                                                            Feel      Inferior to feather quilt (harsh feel)                              ______________________________________                                    

EXAMPLE 2

The same procedure as in Example 1 was repeated except that theviscosity of the epoxysiloxane used in the treating agent A of Example 1was varied as shown in Table 3. The results obtained are also shown inTable 3.

                                      TABLE 3                                     __________________________________________________________________________    Run No. 2-1  2-2 2-3 2-4 2-5 2-6 2-7                                          __________________________________________________________________________    Viscosity of                                                                          500  1,000                                                                             3,000                                                                             8,000                                                                             10,000                                                                            100,000                                                                           150,000                                      epoxysiloxane                                                                 Slickness                                                                     μ s  0.23 0.19                                                                              0.17                                                                              0.18                                                                              0.19                                                                              0.19                                                                              0.24                                         μ d  0.25 0.19                                                                              0.19                                                                              0.19                                                                              0.20                                                                              0.21                                                                              0.26                                         Compression                                                                   elasticity                                                                    Compression                                                                   rate (%)                                                                              68   74  80  78  77  73  68                                           Compression                                                                   recovery (%)                                                                          88   93  97  98  97  92  87                                           Feel    Infer-                   Inferior                                             ior to                   to feather                                           feather                                                                            Similar to feather quilt                                                                          quilt                                                quilt                    (harsh)                                              (harsh)                                                               __________________________________________________________________________

In can be seen from Table 3 that epoxysiloxanes having a viscosity of1,000 to 100,000 centistokes gave especially good results and especiallygood results are obtained when the epoxysiloxane has a viscosity of1,000 to 10,000 centistokes.

EXAMPLE 3

The same procedure as in Example 1 was repeated except that the epoxygroup content of the epoxysiloxane used in the treating agent A inExample 1 was varied as shown in Table 3. The results are also shown inTable 4.

                  TABLE 4                                                         ______________________________________                                        Run No.       3-1       3-2     3-3    3-4                                    ______________________________________                                        Epoxy group content                                                                         0.5       0.6     1.0    3.0                                    (wt. %)                                                                       Slickness                                                                     μ s        0.24      0.20    0.16   0.17                                   μ d        0.25      0.21    0.16   0.16                                   Compression elasticity                                                        Compression rate (%)                                                                        66        73      80     79                                     Compression recovery                                                                        87        92      98     97                                     (%)                                                                           Feel          Inferior  Similar to feather quilt                                            to feather                                                                    quilt                                                                         (harsh)                                                         ______________________________________                                    

EXAMPLE 4

The same procedure as in Example 1 was repeated except that the ratiobetween the α-aminopropyl triethoxysilane and the epoxysiloxane used inthe treating agent of Example 1 was changed as shown in Table 5. Theresults are shown in Table 5.

                  TABLE 5                                                         ______________________________________                                        Run No.    4-1      4-2    4-3  4-4  4-5  4-6                                 ______________________________________                                        Ratio*     0.5      1      5    10   20   30                                  Slickness                                                                     μ s     0.24     0.18   0.18 0.16 0.18 0.25                                μ d     0.25     0.19   0.17 0.16 0.19 0.26                                Compression                                                                   elasticity                                                                    Compression rate                                                                         65       73     79   80   75   68                                  (%)                                                                           Compression                                                                   recovery (%)                                                                             87       93     98   97   94   88                                  Feel       Infer-   Similar to feather                                                                            Inferior                                             ior to   quilt           to                                                   feather                  feather                                              quilt                    quilt                                                (harsh)                  (harsh)                                   ______________________________________                                         *The weight in parts of the epoxysiloxane per part by weight of the           α-aminopropyl triethoxysilane. The other components of the treating     agent were the same as in Example 1.                                     

Good results were obtained when the amount of the epoxysiloxane was 1 to20 parts by weight per part by weight of theα-aminopropyltriethoxysilane.

EXAMPLE 5

The same procedure as in Example 1 was repeated except that each of thefollowing epoxysiloxanes was used instead of the epoxysiloxane in thetreating agent A in Example 1.

Epoxysiloxane-(2) composed of structural units of the following formulae##STR12## having a viscosity of 5,000 centistokes at 25° C. and an epoxygroup content of 1.8% by weight with both ends being trimethylsilylgroup [--Si(CH₃)₃ ].

Epoxysiloxane -(3) composed of structural units of the following formula##STR13## and having a viscosity of 10,000 centistokes at 25° C and anepoxy group content of 2% by weight with both ends being trimethylsilylgroups [--SI(CH₃)₃ ].

The results are shown in Table 6 below.

                  TABLE 6                                                         ______________________________________                                        Run No.              5-1       5-2                                            ______________________________________                                        Treating agents                                                               α-Aminopropyl triethoxysilane                                                                0.5       0.9                                            Epoxysiloxane-(2)    4.9                                                      Epoxysiloxane-(3)              4.5                                            Cetyl phosphate potassium salt                                                                     1.1       1.1                                            Polyoxyethylene (10 Mols)                                                     nonyl phenol ether   0.5       0.5                                            Water                93.0      93.0                                           Slickness                                                                     μ s               0.18      0.16                                           μ d               0.19      0.17                                           Compression elasticity                                                        Compression rate (%) 75        79                                             Compression recovery (%)                                                                           94        96                                             Feel                 Similar to feather                                                            quilt                                                    ______________________________________                                    

EXAMPLE 6

Polyethylene terephthalate having an intrinsic viscosity of 0.62(calculated from the measured value in o-chlorophenol at 35° C) was meltspun and drawn to form a tow with a total denier of 500,000 (singlefiber denier of 3). The tow was immersed in an emulsion of the followingrecipe, squeezed by a stuffer crimper to a pick-up of 6%, dried at 90° Cfor 20 minutes, then heat-treated at 140° C for 30 minutes, and cut to alength of 56 mm.

The number of crimps of the resulting fibers was 9 per 25 mm, and thepercent crimp was 15%. The fibers so treated had the followingproperties.

    ______________________________________                                        Recipe for the treating agent                                                 α-Aminopropyltriethoxysilane                                                                 1.0 parts by weight                                      Epoxysilane (same as in Example 1)                                                                 6.6 parts by weight                                      Cetylphosphate potassium salt                                                                      1.6 parts by weight                                      Polyoxyethylene (10 mols) nonyl                                               phenol ether         0.8                                                      Water                90                                                       Properties of the fibers                                                      Slickness                                                                     μ s               0.17                                                     μ d               0.17                                                     Compression elasticity                                                        Compression rate     82                                                       Compression recovery 92                                                       Feel                 Similar to feather quilt                                 ______________________________________                                    

EXAMPLE 7

Polyethylene terephthalate having an intrinsic viscosity, as calculatedfrom the measured value in o-chlorophenol at 35° C., of 0.62 was meltspun and drawn to form a tow having a total denier of 400,000 consistingof hollow fibers each with 7 denier and a hollowness of 13%. Theresulting tow was treated with the treating agent A in Example 1 in thesame way as in Example 1. The number of crimps of the resulting fiberswas 8 per 25 mm, and the percent crimp was 19%. The fibers so treatedhad the following characteristics.

    ______________________________________                                        Slickness                                                                     μ s           0.16                                                         μ d           0.16                                                         Compression elasticity                                                        Compression rate 78                                                           Compression recovery                                                                           98                                                           Feel             Similar to feather quilt                                     ______________________________________                                    

EXAMPLE 8

Polyethylene terephthalate having an intrinsic viscosity, as calculatedfrom the measured value in o-chlorophenol at 35° C., of 0.65 andpolyethylene terephthalate isophthalate (10 mol% of isophthalic acidcopolymerized therein) were co-spum at a weight ratio of 1:1 using aside-by-side type spinneret, and drawn to 3.3 times the original lengthin warm water kept at 75° C. to form a tow with a total denier of 80,000(a single fiber denier of 6.8). The tow was heat-treated in the relaxedstate in air at 80° C., and dipped in the treating agent A of Example 1.It was then squeezed by a stuffer crimper to a pick-up of 12%, and driedat 80° C. for 30 minutes. It was then heat-treated in the relaxed stateat 160° C. for 30 minutes to develop crimps and heat-set them at thesame time, followed by cutting the tow to a fiber length of 76 mm.

The number of crimps of the resulting fibers was 12 per 25 mm, and thepercent crimp was 19%. The fibers had the following characteristics.

    ______________________________________                                        Slickness                                                                     μ s           0.18                                                         μ d           0.17                                                         Compression elasticity                                                        Compression rate 76                                                           Compression recovery                                                                           98                                                           Feel             Similar to feather quilt                                     ______________________________________                                    

EXAMPLE 9

Modified polyethylene terephthalate having an intrinsic viscosity, ascalculated from the measured value in o-chlorophenol at 35° C., of 0.55and containing 14% by weight of a fire-retardant of the followingformula ##STR14## was melt-spun, and drawn to form a tow with a totaldenier of 400,000 (a single fiber denier of 5.5). The resulting two wasdipped in the treating agent A of Example 1, squeezed by a stuffercrimper to a pick-up of 8%, then subjected to the same treatment as inExample 1.

The resulting fibers gave filling fibers having a soft feel similar tothat of feather quilt and a high level of fire retardancy.

    ______________________________________                                        Slickness                                                                     μ s               0.19                                                     μ d               0.19                                                     Compression elasticity                                                        Compression rate     74                                                       Compression recovery 98                                                       ______________________________________                                    

What we claim is:
 1. Filling organic synthetic fibers coated with aheat-treated product of a treating agent comprising (a) 1 part by weightof an aminosilane of the formula (I) ##STR15## wherein R₁ is a hydrogenatom, an alkyl group containing 1 to 4 carbon atoms, or a phenyl group,R₂ is an alkylene group containing 1 to 4 carbon atoms, and R₃, R₄ andR₅, independently from each other, represent an alkyl group containing 1to 4 carbon atoms,and (b) 1 to 20 parts by weight of an epoxysiloxanecontaining at least one structural unit of the formula (II) ##STR16##wherein R₆ and R₇, independently from each other, represent an alkylgroup containing 1 to 3 carbon atoms, and at least two structural unitsof the formula (III) ##STR17## wherein R₈ is an alkyl group containing 1to 3 carbon atoms or the group ##STR18## R₉ being an alkylene groupcontaining 2 to 5 carbon atoms or a substituted or unsubstitued arylenegroup containing 6 to 10 carbon atoms.
 2. The filling organic syntheticfibers of claim 1 wherein said fibers satisfy the followingrelationships:

    1.5 ≦ D ≦ 10

    10d - 20 ≦ l ≦ 10d + 60

    10 ≦ l

    -3/4d + 10.0 ≦ c.sub.n ≦ -3/4d + 15.5

    15 ≦ c.sub.n + c.sub.d ≦ 32

wherein R is the denier size of the synthetic fibers, L is the length ofthe fibers in mm.
 3. The filling organic synthetic fibers of claim 1wherein said aminosilane is selected from the group consisting ofα-aminopropyl triethoxysilane, α-aminopropyl trimethoxysilane,β-methylaminoethyl triethoxysilane and α-phenylaminopropyltrimethoxysilane.
 4. The filling organic synthetic fibers of claim 1aherein said epoxysioxane has a viscosity of 1,000 to 100,000centistokes at 25° C.
 5. The filling organic synthetic fibers of claim 1wherein said epoxysiloxane contains 0.6 to 10% by weight of epox groupsbased on the total weight thereof.
 6. The filling organic syntheticfibers of claim 1 wherein the proportion of said epoxysiloxane is 1 to18 parts by weight per part by weight of said aminoslilane.
 7. Thefilling organic synthetic fibers of claim 1 wherein the treating agentis in the form of an aqueous emulsion.
 8. The filling organic syntheticfibers of claim 1 wherein the total amount of said aminosilane andepoxysiloxane adhered becomes 0.1 to 3.0% by weight based on the dryweight of the fibers.
 9. The filling organic synthetic fibers of claim 1wherein said organic synthetic fibers are polyester synthetic fibers.